through the root cones of sampled trees. inh The rom these cata. we Seveloped concentration Zsectcrs (CT) for estimating ine average radionuciide is well as coneentraticn that would be expected Irom crops zianted in certain regions vegeration (lear) ~o the concentration in ine edible “puit, Jeter- md trovide a better basis cise soncentration ratios that relate the concentration in the factors mined irom inis survey are more >re- relating concentration in ffo0a 7roda“ets to soil concentrraticn. concentration qo samples within an island or on different islands. or the concentration ia indi- Despite the greater precision of cator species (Scaevola and ‘'2sser- concentraticn factors caiculated from senmidia) to concentrations in food associated vegetation and soil data, crops.” these values still show some variabil ~ A separate report. discusses in ity. This remaining variability can detail the results of the sampiing te accounted for by several factors orogram and the calculation otf CF and acting either alone or in concert. concentation ratio, These factors include differences in: [In brier, the distribution of radionuclides in both e the Bikini and Enewetak environment was nonhomogenous. Soil type, organic content, and chemical characteristics; Radionuclide con- e centracions in soil varied greatly Physicochemical properties of the radionuclides; over distances of only a few feet. @ Soil management practices; The results of our work during this @ irrigation practices; survey verified our thesis that e Physiology, age, and prior his- and tory cf the sampled plants. secause of the wide variability in soil concentration with location, use- One would, in fact, expect to see some ful concentration factors can only be variation in sampling conducted from a calculated from vegetation and soil specific tree merely resulting from data sampled from the exact site. normal biological variability. Concentration factors derived from In addition to the calculation of soil sampled from the root zone of the CF, the data from the large surface~ vegetation under investigation showed soil sampling program? were used to a greatly reduced range of values com- determine average soil concentrations pared with values developed earlier in four regions on Bikini Island and from vegetation and soil samples from in the whole of Eneu Island. different sites but in the same average soil concentrations were then area’’?>> (see also Table 22, this used along with the concentration fac- report). tors to predict the radionuclide -3Q— These